Alarm at 3500 RPM

[Ddmccoy]

Hello. I have a 2005 3100 SCR. Recently purchased. I have a beeping alarm that goes on every time I hit approximately 3500 RPM. Is that something that is settable and the previous owner set it there? Can I turn it off?

[mmwjr]

No it not something you can set, it’s indicating there is an issue. What engines do you have and are they carburetors or fuel injected?

[Ddmccoy]

Hi, I have two Mercruiser 5.0 fuel injected engines. Any ideas on what the alarm could be?

[mmwjr]

If you look at the Mercruiser manual under Documents it has a troubleshooting guide that provides faults based on the number of beeps and the pattern of them.

[Ddmccoy]

In the operation and Maintenance manual, I found the following. The warning will sound with a continuous for the following:
1. Low Oil pressure
2. Temp too high.
An intermittent horn will sound if:
1. Sterndrive oil level is low.

I believe I have a continuous alarm. Not too sure because I lower the throttle right away. When I looked at the oil pressure, I thought it was a bit high. Both were about 70 to 75 psi. Seams kind of high as the gauge only goes to 80. Shouldn't it usually run about half way? I recently had a mechanic change the oil, so I checked it. It looks like there is probably almost a quart too much oil in both engines. Do you think higher than normal pressure can cause an alarm. I am going to remove some oil from both engines.

Regarding the temperature. Both engine gauges showed about 3/4 on the dial. That seams on the higher side too but not sure.

Regarding sterndrive oil. I am not sure where that is to check it.

[Ddmccoy]

Here is a pic of the page where I found the information.

[mmwjr]

Yes remove the excess oil but I think only low oil pressure will cause an alarm. Engine temperature should be 160*F but my gauge shows 175*F even though using an IR temp gun I get the correct reading. The gear lube reservoir is a plastic bottle on the front of the engine. Being that you have fuel injection there should be around 10 fault codes with different beeps. I don’t think any are constant. A Rinda scan tool can read out faults from the ECM.

[Ddmccoy]

Thanks. I will see if I can get that tool.

[Ddmccoy]

Is there an OBD2 port on the boat dome place line that in my car? I have one of those for my car. When I look up the Rinda scan tool it gives me eve OBD2 scanner.

[mmwjr]

Originally Posted by Ddmccoy

Is there an OBD2 port on the boat dome place line that in my car? I have one of those for my car. When I look up the Rinda scan tool it gives me eve OBD2 scanner.

An OBD2 tool won’t work but there is a similar connector for the Rinda tool.

[Ddmccoy]

Ok. Where do I find the connection.

[mmwjr]

Originally Posted by Ddmccoy

Ok. Where do I find the connection.

H
Not certain but it will be near the ECM. I recommend you look at the Mercruiser manual.

[Ddmccoy]

Thanks